title: Control analysis of transition times in metabolic systems.
abstract: The transition time, tau, of a metabolic system is defined as the ratio of the metabolite concentrations in the system, sigma, to the steady-state flux, J. Its value reflects a temporal characteristic of the system as it relaxes towards the steady state. Like other systemic properties, the value of tau will be a function of the enzyme activities in the system. The influence of a particular enzyme activity on tau can be quantified by a Control Coefficient, C tau ei. We show that it is possible to derive a Summation Theorem sigma ni = 1 C tau ei = -1 and a Connectivity Theorem sigma ni = 1 C tau ei.epsilon viSk = -Sk/sigma. We establish a 'sign rule' that predicts the order of positive and negative Control Coefficients in a sequence.
authors.affiliation: Departamento de Bioquímica y Biología Molecular, Facultad de Biología, Universidad de La Laguna, Tenerife, Canary Islands, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Meléndez-Hevia
authors.forename: N V
authors.initials: NV
authors.lastname: Torres
authors.forename: J
authors.initials: J
authors.lastname: Sicilia
authors.forename: H
authors.initials: H
authors.lastname: Kacser
mesh_terms: D004798:Enzymes / Q000378:metabolism*; D007700:Kinetics; D008433:Mathematics; D013997:Time Factors
chemical_list: D004798:Enzymes